Recently, there has been an increasing thrust in the application of internal antennas in wireless communications devices. The concept of an internal antenna stems from the avoidance of using an external radiating element through the integration of the antenna into the communications device itself. Internal antennas have several advantageous features such as being less prone to external damage, a reduction in overall size of the communications device with optimization, and easy portability. In most internal antennas, the printed circuit board (PCB) of the communications device serves as the ground plane of the internal antenna.
A known challenge in antenna design is the balance between the size of the ground plane and the antenna performance. While it is known that there may be optimal dimensions for a ground plane in order to achieve the best antenna performance, such dimensions are not always feasible due to the physical constraints of the device itself as well as potential negative impact on the device aesthetics. Some techniques have been presented to control the ground plane wavemodes in order to achieve improved performance, wherein one or more transversal slots on the ground plane are provided. However, such techniques are known to cause undesirable electromagnetic interference issues in addition to being impractical from the standpoint of the ground plane PCB manufacture.